Editor's Note: In this feature from Stockpickr, we highlight lists of stocks that have made new highs, lows or seen other unusual activity.Biggest % Gainers: Puerto Rico's Doral Financial ( DRL) soared 45%, or 58 cents, closing at $1.88 Monday, following the offer from private bank FBOP to purchase 80% of the company for $610 million. Biggest % Losers: GenVec ( GNVC) dropped 29%, or $1.32, after the Maryland biopharmaceutical company revealed a phase II/III study of its TNFerade product that showed no statistically significant tumor-response difference from standard care alone in pancreatic-cancer patients. The study also found the drug to induce a longer survival rate, but the stock plunged anyway. 52-Week Highs: Life Partner Holdings ( LPHI) reached a 52-week high, after saying late Monday it expected higher-than-expected first-quarter earnings. Latest-Activist-Situations: Viking Global Management, a 7.9% stakeholder in LandAmerica ( LFG), asked the company's board to consider selling the company in a Securities and Exchange Commission filing on Friday. On Monday, the title insurance company's shares rose $2.15, or 2.1%, closing at $105.46. 52-Week Lows: Cray ( CRAY), a Seattle-based supercomputer maker, said revenue would be lower then expected, increasing the probability it will not be profitable during 2007. The stock responded with a 52-week low close of $7.20, falling 9.4%, or 75 cents. Rising on Unusual Volume: Shares of Cadence Design Systems ( CDNS)gained 5.8% and volume was up 475% after reports the software company is in discussion regarding a possible buyout with at least two firms, including Kohlberg Kravis Roberts and The Blackstone Group. Cadence closed up $1.32 to $24.22. Stocks with Unusual Option Activity: Hilton Hotels ( HLT) was experiencing unusual options activity and closed down 0.9% or 31 cents. The company has announced three new development alliances with Caribbean Property Group in Central America and the Caribbean, London & Regional Properties in Russia and Shiva Hotels in the U.K. and Ireland. The new alliances will allow Hilton to introduce 55 new hotels.